Chemical mechanical polishing apparatus

ABSTRACT

An apparatus for polishing a semiconductor wafer using a pad resurfacing arm and an apparatus therefor are disclosed. Embodiments may include providing a semiconductor wafer on a chemical mechanical polishing (CMP) tool, the CMP tool including a polish pad and a pad resurfacing arm which includes a pad cleaning part, a pad conditioning part, and a slurry dispensing part, dispensing a slurry to the polish pad utilizing the pad resurfacing arm, and polishing the semiconductor wafer utilizing the polish pad.

RELATED APPLICATION

The present application is a Divisional application of application Ser.No. 14/300,705, filed on Jun. 10, 2014, which is incorporated herein byreference in its entirety.

TECHNICAL FIELD

The present disclosure relates to chemical mechanical polishing (CMP) ofsemiconductor wafers utilizing a polish pad. The present disclosure isparticularly applicable to preparing and/or resurfacing polish padsutilized in CMP of semiconductor wafers for the 22 nanometer (nm)technology node and beyond.

BACKGROUND

CMP is often utilized for planarizing semiconductor wafer surfaces inthe fabrication of integrated circuits. Such CMP processes typicallyinvolve rubbing the surface of the wafer against a polishing device toremove high spots on the wafer surface. The wafer is held in astationary or rotating fixture while being pressed against a stationaryor rotating polishing pad. Generally, at least one of the pad and thearm are moving with respect to each other to create friction between thepad and wafer for polishing the wafer. The polishing pad is supported ona platen which may be rotated during the CMP process. The polishingsurface of the polishing pad may be constructed from a variety ofmaterials, such as open-cell foam polyurethane or a sheet ofpolyurethane with a grooved surface. The polishing surface is relativelyrough in comparison to the semiconductor wafer surface. A slurry ofpolishing fluid is often introduced to further aid in the CMP process.

The surface of the polishing pad gradually becomes glazed due to theaccumulation of material removed during the polishing process.Accordingly, the pad must be periodically conditioned to restore itsrough surface texture. Such conditioning involves the application of anabrasive surface of a conditioning device against the surface of thepolishing pad to remove the accumulated debris, and it may remove aportion of the polishing pad surface itself. Conditioning will expose arenewed polishing pad surface having characteristics essentially thesame as or similar to a new pad. Commonly, a polishing pad isconditioned after each semiconductor wafer is polished.

Several types of conditioning devices are known in the art, for examplea conditioning disk having a diamond abrasive surface formed thereon.The abrasive surface is rubbed against the polishing pad surface at apredetermined velocity, for a predetermined length of time, with apredetermined amount of force exerted between. The abrasive diamondsurface functions to condition or roughen the surface of the polishingpad. The amount of conditioning may be varied by changing the velocity,time of contact, or force between the conditioning device and thepolishing pad. For instance, the amount of conditioning will increasewith an increased velocity, a lengthened time period, or an increasedforce between the two surfaces.

Too much or too little conditioning will provide undesirable results.CMP specifications are tightening as the semiconductor industryprogresses to manufacturing semiconductor wafers at smaller technologynodes, such as 22 nm and 14 nm nodes. Polish pad resurfacing andpreparation processes, such as slurry distribution, are being developedfor manufacturing at smaller technology nodes and 450 mm wafers.Controlled conditioning of a polish pad in CMP is commonly utilized tocreate more consistent polish conditions throughout a CMP usabilitylifetime of a polish pad.

Current polish pad resurfacing and preparation processes have severallimitations and drawbacks. One limitation is that a polish pad is oftennot prepared and/or resurfaced consistently over the whole surface ofthe pad. For example, a polish pad is often conditioned utilizing arotating conditioning disc on a conditioning arm moving at differentialsweeping motions and speeds to resurface the polish pad. The sweep speedis often zero at points where the sweeping motion is reversed.Alternatively, it may be elevated at other locations of a sweepingmotion, such as at a periphery of a “donut” hole at the center of anorbital sweeping motion. The differential sweeping motions and speedscommonly result in differential removal rates of the unconditioned padat turning points of the sweeping motion and at areas of the padconditioned at higher sweeping speeds.

Another limitation is that conditioning arms currently utilized inpolish pad resurfacing and preparation processes often do not providefor control or measurement of dynamic or differential downward forcesapplied to the polish pad through the arms. Instead, downward forcesthat are unitary and static in nature are commonly applied through thearms via a pneumatic system. Often the unitary static downward forcesapplied through the arms are difficult to measure, such as by utilizinga load cell.

Another limitation is that arms currently utilized in polish padresurfacing and preparation processes, such as a conditioning arm, areoften mechanically unstable due to the high wearing out of bearings andother mechanical parts associated with moving the arms. Anotherlimitation is that separate mechanical parts are required for padconditioning and pad cleaning. A conditioning arm generally has nocleaning capability for cleaning a polish pad. Similarly, a cleaning armor other means for cleaning a polish pad, such as an atomizer, generallyhas no pad conditioning capability.

A need therefore exists for methodology enabling (1) consistentpreparation and/or resurfacing over a whole surface of a polish pad in aCMP tool, (2) control and/or measurement of dynamic and/or differentialdownward forces applied to a polish pad in a CMP tool, (3) mechanicalstability regarding mechanical parts utilized in a CMP tool and (4) areduction in the number of separate mechanical parts in a CMP toolutilized for preparing and/or resurfacing a polish pad in a CMP process,and an apparatus therefore.

SUMMARY

An aspect of the present disclosure includes a method includingproviding a pad resurfacing arm including a pad cleaning part, a padconditioning part, and a slurry dispensing part.

Another aspect of the present disclosure includes an apparatus includinga pad resurfacing arm including a pad cleaning part, a pad conditioningpart, and a slurry dispensing part.

Additional aspects and other features of the present disclosure will beset forth in the description which follows and, in part, may be apparentto those having ordinary skill in the art upon examination of thefollowing or may be learned from the practice of the present disclosure.Advantages of the present disclosure may be realized and obtained asparticularly pointed out in the appended claims.

According to the present disclosure, some technical effects may beachieved, in part, by a method including providing a semiconductor waferon a CMP tool, the CMP tool including a polish pad, and a padresurfacing arm. Another aspect includes a pad cleaning part, a padconditioning part, and a slurry dispensing part in a method, the methodfurther including dispensing slurry to the polish pad utilizing the padresurfacing arm, and polishing the semiconductor wafer utilizing thepolish pad.

Another aspect includes conditioning the polish pad, utilizing the padresurfacing arm. Yet another aspect includes cleaning the polish pad,utilizing the pad resurfacing arm. Other aspects include conditioningthe polish pad, utilizing the pad resurfacing arm, and cleaning thepolish pad, utilizing the pad resurfacing arm. A further aspect includesutilizing the pad resurfacing arm by rotating the pad resurfacing arm.An additional aspect includes the pad resurfacing arm being cylindrical.Yet another aspect includes the pad resurfacing arm being conical. Stillanother aspect includes utilizing the pad resurfacing arm by sliding thepad resurfacing arm on the polish pad. A further aspect includes the padresurfacing arm including guides of a plastic material. An additionalaspect includes utilizing the pad resurfacing arm by applying differentlevels of force to the polish pad from different locations of the padresurfacing arm.

Another aspect of the present disclosure includes an apparatus includinga CMP tool, the CMP tool including a polish pad and a pad resurfacingarm, which includes a pad cleaning part, a pad conditioning part, and aslurry dispensing part.

Another aspect includes the CMP tool being configured to rotate the padresurfacing arm. Yet another aspect includes the CMP tool beingconfigured to sweep the pad resurfacing arm over the polish pad. Stillanother aspect includes the apparatus including a flatness monitoringarm. An additional aspect includes the pad resurfacing arm beingcylindrical. Yet another aspect includes the pad resurfacing arm beingconical. A further aspect includes the CMP tool being configured toslide the pad resurfacing arm on the polish pad. Another aspect includesthe pad resurfacing arm including guides of a plastic material. Yetanother aspect includes the CMP tool being configured to apply differentlevels of force to the polish pad from different locations of the padresurfacing arm. A further aspect includes the CMP tool being configuredto rotate the pad resurfacing arm on the polish pad. Yet another aspectincludes the CMP tool being configured to rotate the pad resurfacingarm, vertically, on the polish pad.

Additional aspects and technical effects of the present disclosure willbecome readily apparent to those skilled in the art from the followingdetailed description wherein embodiments of the present disclosure aredescribed simply by way of illustration of the best mode contemplated tocarry out the present disclosure. As will be realized, the presentdisclosure is capable of other and different embodiments, and itsseveral details are capable of modifications in various obviousrespects, all without departing from the present disclosure.Accordingly, the drawings and description are to be regarded asillustrative in nature, and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawing and in whichlike reference numerals refer to similar elements and in which:

FIG. 1 schematically illustrates a top view of a CMP tool, in accordancewith an exemplary embodiment;

FIG. 2 schematically illustrates a side view of a pad resurfacing arm,in accordance with an exemplary embodiment;

FIG. 3 schematically illustrates a side view of a CMP tool, inaccordance with an exemplary embodiment;

FIG. 4 schematically illustrates a process flow for polishing asemiconductor wafer, in accordance with an exemplary embodiment; and

FIG. 5 schematically illustrates a process flow for polishing asemiconductor wafer, in accordance with an exemplary embodiment.

DETAILED DESCRIPTION

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of exemplary embodiments. It should be apparent, however,that exemplary embodiments may be practiced without these specificdetails or with an equivalent arrangement. In other instances,well-known structures and devices are shown in block diagram form inorder to avoid unnecessarily obscuring exemplary embodiments. Inaddition, unless otherwise indicated, all numbers expressing quantities,ratios, and numerical properties of ingredients, reaction conditions,and so forth used in the specification and claims are to be understoodas being modified in all instances by the term “about.”

The present disclosure addresses and solves the current problem(s) of(1) inconsistent preparation and/or resurfacing over a whole surface ofa polish pad in a CMP tool, (2) lack of control and/or measurement ofdynamic and/or differential downward forces applied to a polish pad in aCMP tool, (3) mechanical instability regarding mechanical parts utilizedin a CMP tool and (4) a large number of mechanical parts in a CMP toolutilized for preparing and/or resurfacing a polish pad in a CMP process.In accordance with embodiments of the present disclosure, a process usesa CMP tool including a polish pad and a pad resurfacing arm, the padresurfacing arm including a pad cleaning part, a pad conditioning part,and a slurry dispensing part.

Methodology in accordance with embodiments of the present disclosure mayinclude providing a semiconductor wafer on a CMP tool, the CMP toolincluding a polish pad, and a pad resurfacing arm including a padcleaning part, a pad conditioning part, and a slurry dispensing part. Aslurry is dispensed to the polish pad utilizing the pad resurfacing arm.Then, the semiconductor wafer is polished utilizing the polish pad.

Still other aspects, features, and technical effects will be readilyapparent to those skilled in the art from the following detaileddescription, wherein preferred embodiments are shown and described,simply by way of illustration of the best mode contemplated. Thedisclosure is capable of other and different embodiments, and itsseveral details are capable of modifications in various obviousrespects. Accordingly, the drawings and description are to be regardedas illustrative in nature, and not as restrictive.

Adverting to FIG. 1, in accordance with an exemplary embodiment, atop-down view of a CMP tool 100 is illustrated including a padresurfacing arm 101 on a polish pad 103 resting upon a platen (notshown) below the polish pad 103. The CMP tool 100 also includes a waferholder 105, which may be rotating or stationary (illustrated asrotating), holding a semiconductor wafer below (not shown) in contactwith polish pad 103, which may be rotating or stationary, under thesemiconductor wafer. The pad resurfacing arm 101 is movable orstationary over the polish pad 103. In general, at least one of the pad103 and the arm 101 are moving with respect to each other to generatefriction between the pad 103 and a wafer. As depicted in FIG. 1, thelength of arm 101 extends from the outer periphery of polish pad 103 andacross the center of the polish pad 103. The arm 101 may slide androtate in such a manner that the whole surface of the polish pad 103 iscleaned, conditioned or dispensed slurry by the arm 101.

The arm 101 may rotate in place, or slide in different directions overthe polish pad 103, such as in an arc movement or an orbital movementover a partial or a whole surface of the polish pad 103. The padresurfacing arm 101 may be constructed of various materials, such asmetal (e.g., aluminum), metal alloy (e.g., steel) and may includeguides, for sliding on the polish pad 103, made with a lightweightmaterial, such as a plastic material (e.g., thermoplastic polymers suchas polyether ether ketone (i.e., PEEK), poly-p-phenylene sulfide (i.e.PPS), and silicon carbide (i.e., SiC)). The pad resurfacing arm 101 mayutilize a variety of structural variations and may be, for example,cylindrical and/or conical, or in a box structure in the CMP tool 100covering partially or fully a surface of the polish pad 103.

The pad resurfacing arm 101 includes a pad cleaning part 107, such as anatomizer or a spray nozzle for delivering a cleaning fluid under highpressure, such as distilled or ultra-purified water treated withnitrogen gas, to the polish pad 103. The pad resurfacing arm 101 alsoincludes a pad conditioning part 109, which may be made from hardmaterials such as diamond or silicon carbide peaks to form an abrasivesurface which may include, for example, a rotating or oscillatingsurface of the arm 101, an internal disc or other mechanism for applyingmotion to the abrasive surface of pad conditioning part 109 with respectto the polish pad 103. The pad resurfacing arm 101 also includes aslurry dispensing part 111 for dispensing polishing slurry to the polishpad for polishing the semiconductor wafer. The slurry dispensing part111 includes one or more slurry outlets, for example five outlets, fordispensing slurry to the polish pad. The outlets may be fixed or movableon the slurry dispensing part 111.

Adverting to FIG. 2, in accordance with an exemplary embodiment, a sideview of a pad resurfacing arm 200 is illustrated. The pad resurfacingarm 200 is conical in shape and includes different locations, such aslocation 201 and 203 through which different levels of force may beapplied to a polish pad for purposes such as conditioning and/orcleaning. The local forces may be controlled using local implementationof the force, such as by a load cell for each location on the armutilizing a strain gauge attuned for each load cell. The load cells orother implementation may utilize a variety of power sources, including,but not limited to, magnetic levitation, an electric motor, pneumaticpressure, and mechanical drives.

Adverting to FIG. 3, in accordance with an exemplary embodiment, a CMPtool 300 includes a pad resurfacing arm 301 that may be, for example,cylindrical in shape. FIG. 3 illustrates the whole arm 301 rotating, butwith differential downward forces as depicted by the separate downwardarrows at different locations of the arm. A semiconductor wafer 303 maybe held in a wafer holder 305 (stationary or rotating) which may bemoved against or into contact with a platen 307 covered with a polishingpad 309. The platen 307 may be rotated by a motor 313 connected to apower supply 315. The polish pad surface 311 of the polishing pad 309receives a slurry dispensed from the pad resurfacing arm 301 forpolishing the semiconductor wafer 303. Also, at least periodically, thepad resurfacing arm cleans debris from the polish pad surface 311, suchas by spraying or atomizing the polish pad surface 311 with a cleaningfluid, and/or conditions the polish pad 309 to retain a desired level ofroughness in the polish pad surface 311. To accomplish the dispensing ofslurry, conditioning, and cleaning, the pad resurfacing arm 101 includesa part for each of these functions such as described above with respectto FIG. 1.

Pad resurfacing arm 301 is illustrated schematically as being connectedto a pneumatic actuator 317 for providing horizontal and verticalmovement of the arm 301, as well as for providing a selected amount offorce between the arm 301 and the polishing pad surface 311 during, forexample, a conditioning operation. Pneumatic actuator 317 may be poweredby a source of compressed gas 319 controlled by regulator 321. Theresurfacing arm 301 may alternatively include a device powered bymagnetic levitation, an electric motor, and other mechanical drives forarm 301, which may have one or more separately rotatable abrasivesurfaces, an abrasive surface formed on a conditioning wheel, or othersuch variations as may be known in the art.

It is known that the conditioning performance of the resurfacing arm 301is a function of the relative velocity between an abrasive surface onthe arm 301 and the surface 311 of the polishing pad 309. It is alsoknown that the conditioning performance is a function of the compressiveforce between these two surfaces, and a function of the length of timethat the two surfaces remain in contact. Furthermore, the conditioningperformance is a function of the roughness of the abrasive surface onthe arm 301. The conditioning performance will increase as the velocitybetween the surfaces is increased, as the compressive force between thesurfaces is increased, and as the length of time of contact between thesurfaces is increased.

The CMP tool 300 with the pad resurfacing arm 301 of FIG. 3 includes acontroller 323 adapted to control the cleaning, conditioning, anddispensing of slurry in a manner sufficient to provide for thesefunctions over a desired area of the polish pad surface 311. Controller323 may be a microprocessor or any sort of electromechanical deviceknown in the art for controlling a process. Controller 323 receives asan input a signal 325 from an ampere meter 327 associated with the powersupply 315 and motor 313. Ampere meter 327 is adapted to measure thepower being supplied to motor 313 and to produce a corresponding signal325. Motor 313 may be powered by another energy source, such as apneumatic motor powered by compressed gas, in which case an appropriateequivalent sensor may be provided in lieu of ampere meter 327 formeasuring the power or rate of energy delivery to such motor.

In addition to signal 325, or as an alternative thereto, controller 323may receive one or more input signals 329 from one or more strain gauges331 attached to resurfacing arm 301 or other structure connected to theresurfacing arm 301. The one or more strain gauges 331 are adapted tomeasure the deflections of arm 301 at different locations in the armcaused by the friction forces generated between the one or morelocations of arm 301 and polish pad surface 311. Both signals 325, 329correspond in magnitude to the friction forces generated between thepolish pad surface 311 and locations of the resurfacing arm 301. As afriction force increases, the amount of deflection at a location of arm301 increases, as well as the amount of power that must be supplied tomotor 313 in order to maintain a selected rotation or other movementspeed of arm 301 on polish pad 309. Accordingly, as the conditioningperformance of the resurfacing arm 301 changes as a result of uses of anabrasive surface of the resurfacing arm 301 or other conditions ofpolish pad 309, such as a need for cleaning a corresponding change insignals 325, 329 is realized.

In order to modify the conditioning, slurry dispensing, and/or cleaningto account for a change in the polish pad surface 311, such as slurrybuildup, or conditioning needed in a specific area of the polish padsurface 311, controller 323 may be programmed to provide signalsnecessary to control one or more variables, such as the velocity and/orrotational movement between polish pad surface 311 and resurfacing arm301, the selected movement direction(s), the length of time of thecleaning, conditioning and/or slurry dispensing operations, and thecompressive force between the polish pad surface 311 and the resurfacingarm 301. To accomplish such control, controller 323 may generate acontrol signal 331 connected to regulator 321 to control the amount ofdown force applied between the resurfacing arm 301 and the polishing pad309 by pneumatic actuator 317. Controller 323 may also or alternativelyprovide a control signal 333 connected to motor 313 to control the speedof operation of motor 313. Furthermore, controller 323 may include aninternal or external timer 335 associated with output signals 331, 333for controlling the duration of conditioning, cleaning and slurrydispensing operations by the resurfacing arm 301, for example inresponse to signals from a conventional flatness monitoring arm (notshown for illustrative convenience).

Adverting to FIG. 4, a process 400 is illustrated which may be utilizedfor polishing a semiconductor utilizing CMP tool 100, according to anexemplary embodiment. The steps of process 400, and other methodsdescribed herein, are described by way of example with the CMP tool 100.

After process start, at step 401, a semiconductor wafer is provided onthe CMP tool 100, including polish pad 103 and pad resurfacing arm 101.The pad resurfacing arm 101 includes the pad cleaning part 107, the padconditioning part 109, and the slurry dispensing part 111. The CMP tool100 also includes holder 105 holding the semiconductor wafer on thepolish pad 103.

At step 403, the slurry dispensing part 111 in the pad resurfacing arm101 dispenses slurry to the polish pad 103, such as for polishing thesemiconductor wafer which is held in the wafer holder 105.

At step 405, CMP tool 100 is utilized to polish the semiconductor waferheld in the wafer holder 105 by moving the semiconductor wafer while incontact with the polish pad 103. The wafer may be moved over the polishpad in various ways, such as by rotating the wafer holder 105, orrotating the polish pad 103 under the wafer, or combinations thereof.

Once the wafer has been polished sufficiently, if, at 407, another waferis to be planarized, the process 400 may begin again at step 401.Otherwise, after 407, the process ends. Although shown as requiring aslurry dispensing step prior to polishing for each wafer, it is possibleto reuse a slurry for polishing multiple wafers rather than dispensingslurry for each wafer.

Adverting to FIG. 5, an expanded process 500 is illustrated which may beutilized for polishing a semiconductor utilizing CMP tool 100, accordingto an exemplary embodiment.

After process start, at step 501, a semiconductor wafer is provided onthe CMP tool 100, including polish pad 103 and pad resurfacing arm 101.The pad resurfacing arm 101 is cylindrical in shape and include guidesmade of a plastic, such as PEEK or PPS, and a hard conditioningmaterial, such as a silicon carbide material. The arm 101 includes padcleaning part 107, pad conditioning part 109, and slurry dispensing part111. The CMP tool 100 also includes wafer holder 105 holding thesemiconductor wafer on the polish pad 103.

At step 503, the pad cleaning part 107 of the pad resurfacing arm 101 isutilized to clean the polish pad 103, such as by spraying cleaning fluidon a surface of the polish pad 103 utilizing an atomizer within the padcleaning part 107. Pad cleaning step 503 may be performed in-situ orex-situ. As indicated in FIG. 5, pad cleaning step 503 may be omittedfor one or more wafers. However, if it is desired that wafers bepolished with equivalent conditions, according to an example, thecleaning step is preferably not omitted. The pad cleaning 503 isfollowed by a pad conditioning step 505. However, the pad cleaning andthe pad conditioning may occur in reverse order or may overlap orcoincide, for example, provided that water from the pad cleaning isremoved before dispensing a slurry for polishing the wafer. According toan example, it is possible to reuse the slurry for additional wafers,such as, for example, when pad cleaning is not done.

At step 505, the pad conditioning part 109 of the pad resurfacing arm101 is utilized to condition the polish pad 103 while rotating andsliding the arm 101 and/or applying different levels of force to thepolish pad 103 from different locations of the arm 101. As indicated inFIG. 5, if no pad cleaning step is utilized, pad conditioning step 505may also be omitted for one or more wafers. However, again for allwafers to be polished with the same conditions, the conditioning stepshould not be omitted. When step 505 is utilized, the polish pad 103 isconditioned in a pad conditioning step 505 followed by a slurrydispensing step 507.

At step 507, the slurry dispensing part 111 in the pad resurfacing arm101 dispenses slurry to the polish pad 103, for polishing thesemiconductor wafer which is held in the wafer holder 105. Althoughshown as separate steps in FIG. 5, pad conditioning step 505 and slurrydispensing step 507 may occur together.

At step 509, CMP tool 100 is utilized to polish the semiconductor waferheld in the wafer holder 105 by moving the semiconductor wafer while incontact with the slurry and the polish pad 103. The wafer may be movedover the polish pad in various ways, such as by rotating the waferholder 105, or rotating the polish pad 103 under the wafer, orcombinations thereof.

Once the wafer has been polished sufficiently, if, at 511, another waferis to be planarized, the process 500 may begin again at step 501.Otherwise, at 511, the process ends.

The embodiments of the present disclosure can achieve several technicaleffects, such as (1) consistent preparation and/or resurfacing over awhole surface of a polish pad in a CMP tool, (2) control and/ormeasurement of dynamic and/or differential downward forces applied to apolish pad in a CMP tool, (3) mechanical stability regarding mechanicalparts utilized in a CMP tool and (4) a reduction of mechanical parts ina CMP tool utilized for preparing and/or resurfacing a polish pad in aCMP process. The present disclosure enjoys industrial applicability inany of the semiconductor arts. For example, the present disclosureenjoys industrial applicability associated with the designing andmanufacturing of any of various types of highly integrated semiconductordevices used in microprocessors, smart phones, mobile phones, cellularhandsets, set-top boxes, DVD recorders and players, automotivenavigation, printers and peripherals, networking and telecom equipment,gaming systems, and digital cameras.

In the preceding description, the present disclosure is described withreference to specifically exemplary embodiments thereof. It will,however, be evident that various modifications and changes may be madethereto without departing from the broader spirit and scope of thepresent disclosure, as set forth in the claims. The specification anddrawings are, accordingly, to be regarded as illustrative and not asrestrictive. It is understood that the present disclosure is capable ofusing various other combinations and embodiments and is capable of anychanges or modifications within the scope of the inventive concept asexpressed herein.

What is claimed is:
 1. An apparatus comprising: a chemical mechanicalpolishing (CMP) tool, the CMP tool comprising: a polish pad; a waferholder positioned over the polish pad; and a pad resurfacing arm overthe polish pad and having a length extending from an outer periphery ofthe polish pad and across a center of the polish pad, the padresurfacing arm comprising: a pad cleaner, a pad conditioner, and aslurry dispenser, wherein the CMP tool is configured to apply differentlevels of force to the polish pad from different locations of the padresurfacing arm.
 2. The apparatus according to claim 1, wherein the CMPtool is configured to rotate the pad resurfacing arm.
 3. The apparatusaccording to claim 1, wherein the CMP tool is configured to sweep thepad resurfacing arm over the polish pad.
 4. The apparatus according toclaim 1, further comprising: a flatness monitoring arm.
 5. The apparatusaccording to claim 1, wherein the pad resurfacing arm is cylindrical. 6.The apparatus according to claim 1, wherein the pad resurfacing arm isconical.
 7. The apparatus according to claim 1, wherein the CMP tool isconfigured to slide the pad resurfacing arm on the polish pad.
 8. A toolcomprising: a polish pad; a wafer holder positioned over the polish pad;and a pad resurfacing arm over the polish pad and having a cylindricalor conical shape with a length extending from an outer periphery of thepolish pad and across a center of the polish pad, the pad resurfacingarm comprising: a pad cleaner, a pad conditioner, and a slurrydispenser, wherein the tool is configured to apply different levels offorce to the polish pad from different locations of the pad resurfacingarm.
 9. The tool according to claim 8, wherein the pad resurfacing armis configured to slide on the polish pad.
 10. The tool according toclaim 8, wherein utilizing the pad resurfacing arm is configured toapply different levels of force to the polish pad from differentlocations of the pad resurfacing arm.
 11. The tool according to claim 8,wherein the tool is a chemical mechanical polishing (CMP) toolconfigured to rotate the pad resurfacing arm.
 12. The tool according toclaim 8, further comprising: a flatness monitoring arm.
 13. The toolaccording to claim 8, wherein the pad resurfacing arm is cylindrical.14. The tool according to claim 8, wherein the pad resurfacing arm isconical.
 15. An apparatus comprising: a chemical mechanical polishing(CMP) tool, the CMP tool comprising: a polish pad; a wafer holderpositioned over the polish pad; and a cylindrical pad resurfacing armpositioned over the polish pad and having a length extending from anouter periphery of the polish pad and across a center of the polish pad,the pad resurfacing arm further comprising: a pad cleaner, a padconditioner, and a slurry dispenser, wherein the CMP tool is configuredto apply different levels of force to the polish pad from differentlocations of the pad resurfacing arm.
 16. The apparatus according toclaim 15, further comprising: a flatness monitoring arm.